The present invention relates to a tracking information detecting device used for a video signal recorder/reproducer.
A video signal recorder/reproducer such as a video tape recorder or a video disc apparatus has recently been widely used. One of the factors for determining the quality of a picture in the recorder/reproducer of this type is the tracking accuracy of its reproducing head. Heretofore, a variety of devices have been proposed to detect the tracking error of a reproducing head. In one of the detecting devices, one or two detecting heads are provided adjacent to a reproducing head so as to check the track on one side or the tracks on both sides adjacent to the track which is being reproduced. The output of the detecting head or heads will vary in response to the displacement of the tracking. Since the detecting heads are so provided in detecting devices of this type, the mechanical structure of such a detecting device becomes complicated and the device becomes expensive. This device has another disadvantage in that it is difficult to apply to an azimuth recording type recorder/reproducer. In another of the detecting devices, pilot signals of different frequencies are superposed on each track of a video signal in the recorder. In this device, the frequency of the pilot signal is detected at the time of reproducing the track to obtain tracking error information. According to this device, it is not necessary to provide a detecting head, but it is possible that a certain frequency of the pilot signal might interfere with the video signal. As a result, a beat will be produced by the pilot signal, and thus, accurate tracking information cannot be obtained.